Abstract: A process for thermal treatment of solid particles in a fluidized bed wherein the solid particles by thermal treatment form a lighter weight fraction and a heavier weight fraction, relative to the total contents of the bed. The process is characterized by use of a selective heavier particle discharge conduit in the sloping bed support and maintenance of a discrete fluid fueled flame in close proximity to and above the opening to the heavier particle discharge conduit. This forms a higher temperature zone in and surrounding the flame, at least about 100.degree. F. higher than the remainder bed temperature. Circulation of solid particles through the flame and its surrounding higher temperature region is promoted both by directing of fluidization gas jets in the fluidized bed support and by the jetting action of the upwardly flowing heavier particle discharge gas.

Abstract: A process for thermal treatment of solid particles in a fluidized bed wherein the solid particles by thermal treatment form a lighter weight fraction and a heavier weight fraction, relative to the total contents of the bed. The process is characterized by use of a selective heavier particle discharge conduit in the sloping bed support and maintenance of a discrete fluid fueled flame in close proximity to and above the opening to the heavier particle discharge conduit. This forms a higher temperature zone in and surrounding the flame, at least about 100.degree. F. higher than the remainder bed temperature. Circulation of solid particles through the flame and its surrounding higher temperature region is promoted both by directing of fluidization gas jets in the fluidized bed support and by the jetting action of the upwardly flowing heavier particle discharge gas.